Kelly said he did not know if the reports were true, but added that he supports attempts to foster communication with Russia.

"Any channel of communication, back or otherwise, with a country like Russia is a good thing," Kelly said. "I doesn't bother me."

He said the US could not necessarily trust messages from Russia, but would include this distrust as another "data point" in White House deliberations.

Kushner has drawn increased scrutiny as reports have emerged about his contacts with the Russian ambassador and a Russian banking representative. CNN reported on Thursday that the FBI was looking into Kushner's many roles on both Trump's transition team and in the White House.

Sen. Lindsey Graham, a Republican from South Carolina, said on CNN's "State of the Union" that he was skeptical of the back-channel story because he did not trust Russian officials.

"You've got the ambassador to Russia reporting back to Moscow on an open channel," Graham said. "I don't trust this story as far as I can throw it. ... The whole storyline is suspicious."

Rep. Adam Schiff, the top Democrat on the House intelligence committee, said Sunday on ABC that US officials need to get to the bottom of the allegations against Kushner, including if Kushner was not honest about his Russia contacts during the security clearance process. Schiff said that if he had confirmation of the allegations, Kushner's security clearance should be revoked.

"I do think there ought to be a review of his security clearance to find out whether he was truthful, whether he was candid," Schiff said. "If not then there's no way he can maintain that kind of a clearance."

Former Director of National Intelligence James Clapper, in an interview on NBC's "Meet the Press," said he would not confirm the stories about Kushner's conversations, but added that he was "very concerned" about reports of the Trump administration approaching Russia "from a theoretical standpoint."